You can leash train a cat, but you need to use a harness instead. When I was very, very young and stupid (we're talking 7 or 8 here) I tried to put a makeshift leash on the outdoor stray cat and all that happened was she took off with it on. And then I was freaking out and my mother was freaking out because, you know, what if she got stuck on something and managed to choke to death. So then I had to go exploring around this gigantic acre or so of land that was our backyard trying to find her. I hopped the fence into my neighbor's yard, thinking I'd find her in the bushes. The moment my feet touched the ground the neighbor's dog charged me in attack. I'm not sure how I did that at the height that I was at back then, but that was the one and only time in my life I was able to scale a fence in a single bound.

There you have my insane 9am rant about my personal encounters of making mistakes with leashes and suddenly defying the laws of gravity.